This is something I've been working on the last few weeks. We've run Kiwi Syslog Server forever, but have never done anything with it other than collect logs. I decided to try and implement some physical security measures using the reporting functionality of Kiwi Syslog Server.
Statements in bold are specific Cisco commands. I'm not going to give away the farm, but I can direct you towards what I use.
I'm not going to say this is the best way to do this. I just saying this is what I've done.
First assumption: you already have syslogging turned on and working.
Good. Got that done? It can be troublesome, but skipping past that.
Second, you ought to have some sort of scheme as to how you have everything plugged into your routers and switches. Let's hope you already have that.
That 65 hour project done? Good. Moving on.
The purpose of having the first two things done is so you can limit the length of the exclusion list on your Syslog Server. There are always some oddballs, but those can be accounted for without too many exclusions in the list.
I hope you also have hostnames that identify the device decently. That makes writing the catch statements easier. I call them catch statements, but really that is inaccurate. They are text based filters.
What I've learned about writing these filters is you need to be simplistic in filter design. You can have up to 100 different filters per action, so don't try and filter a complex statement in one filter. Use multiples. For example, I have one filter built that limits to switch traffic. Should I need to write anything else that is based solely on switches, I can then copy that one filter and know I'm now working only on switches.
For physical security on switches, any unused port is in a shutdown state. All other ports use MAC address sticky. Because they use MAC address sticky, I alert on any time there is a port-security violation. So within two minutes of plugging in a cable to the switch, I'm aware.
For routers, I'm aware of what ports should be used. I then monitor all router ports for up/down states. So, should you plug into a router, the syslog will see the port status change and alert. That can then be correlated with DVRs in the store to identify who plugged in, and with the port status down message, you get an indication of how long the person was plugged in.
The other option is to have the router ports shutdown as well. Depending on the day, I can lean either direction.
If you are going to leave the ports on, you need to be physically blocking them off with a tamper sticker. I'd almost say use a tamper sticker anyways.
As for all the other port up/down messages, I would run those though whatever network analytic software you use.
I'm sure there are better ways to do physical security. Locked rooms, locked doors, and cages come to mind. But operationally, that's not always possible. So you have to work with what you've got. And despite being critical to operation, people who build buildings generally don't want to dedicate an entire lockable room to things that aren't sold out the front door.
A blog about the things that interest me. Includes random thoughts, Cisco, programming, and business related stuff from convenience store world.
Tuesday, November 4, 2014
Monday, November 3, 2014
Active Directory and Content Adviser part 2
Found a solution to the problem I talked about the last post. The answer was use a proxy server. The proxy server is actually a file pointing to the local host with a bit of scripting involved that either returns the outside interface "proxy server unavailable". Which works out pretty well, because you get the effect of blocking the Internet. The proxy file is located on a read-only network share, and is copied to the computer whenever the user logs in. So even if the Internet goes down, you still have the old proxy file. And when the Internet comes up, you get the latest, greatest version.
That seems to work a lot better in theory than content adviser. And for some reason I want to spell adviser as "advisor". Anyways.
The hard part was need to rebuild the IE auto-install to get the proxy settings into the Internet Options control panel, and turning off Content Adviser. That required removing the computer from the domain, use "Turn Windows Features On and Off" to remove and re-add IE 11 with none of the IEAK options set. The rejoin the domain, and then the IEAK version to have the proxy file working and in place.
The great benefit of this approach is the proxy file works with Chrome as well.
But there are certain programs we use that are hard coded to use Internet Explorer, so there's no option of permanently going away from that.
Yay. Now all I have to do is get the logon script working properly, and everything will be great. Did I mention I'm deploying the computer Monday afternoon?
My Active Directory learning was from this book: Windows Server 2008 Active Directory Configuration.
That seems to work a lot better in theory than content adviser. And for some reason I want to spell adviser as "advisor". Anyways.
The hard part was need to rebuild the IE auto-install to get the proxy settings into the Internet Options control panel, and turning off Content Adviser. That required removing the computer from the domain, use "Turn Windows Features On and Off" to remove and re-add IE 11 with none of the IEAK options set. The rejoin the domain, and then the IEAK version to have the proxy file working and in place.
The great benefit of this approach is the proxy file works with Chrome as well.
But there are certain programs we use that are hard coded to use Internet Explorer, so there's no option of permanently going away from that.
Yay. Now all I have to do is get the logon script working properly, and everything will be great. Did I mention I'm deploying the computer Monday afternoon?
My Active Directory learning was from this book: Windows Server 2008 Active Directory Configuration.
Friday, October 31, 2014
Active Directory makes me something something....
Been working on Windows Server 2008 Active Directory automatic installation. All I want to do is use automatic installation of IE 11 with a specific Content Adviser set. But no. When I update Content Adviser using the IE Automated Installation Kit, it doesn't update Content Adviser. It doesn't even install.
Great.
Back to beating on the same problem.
Great.
Back to beating on the same problem.
Wednesday, October 29, 2014
Introduction to Networking Chapter 3 notes
Chapter 3 notes from Introduction to Networking
Network protocols and communication
Rather than adopt new standards and rebuilding the wheel, the network industry has developed a framework
-use of accepted models
All communication has 3 elements
-sender or source
-receiver or destination
-channel, the medium over which the message travels
transmission governed by protocols
-specific to type of communication
protocols necessary for effective communication
-specific to characteristics of communication method
-must be followed to be successfully delivered and understood
-identify sender and receiver
-common language and grammar
-speed and timing of delivery
-confirmation of acknowledgement requirements
Network protocols define
-message encoding
-msg formatting and encapsulation
-msg size
-msg timing
-msg delivery options
message encoding
-process of converting into another form for transmission
decoding - reverse of encoding; used to interpret
message formats
-depend on msg
-channel
if destination address and formatting wrong, then msg is not delivered
-computer format called a frame
frame acts like an envelope
message size
-large messages broken into smaller
message timing
access method- where you can send
flow control - how much and how fast
response timeout - reaction according to no answer
rules of communication
message delivery options
1 to 1 - unicast
1 to many - multicast
1 to all - broadcast
protocol suite - a group of interrelated protocols necessary to communicate
visualized as a stack
lower layers - transmit data
upper layers - focused on content
application protocol
transport protocol
internet protocol
network access protocol
standards organizations
-open standards encourage competition and innovation
-prevent monopoly
-standards organizations write rules in order to maintain an open internet
-vendor neutral
-non-profit includes ISCO, IAB, IETF, IEEE, ISO
ISOC - promotes open development
-evolution
-world wide use
IAB - responsible for overall management
-development of standards
-oversight of architecture and protocols
IETF - develop, update maintain internet and TCP/IP technologies
-produce RFC
IESO - technical management of the IETF
IRTF - focused on long term research
IEEE - wide range of standards
-wireless
-MAC for wired ethernet
ISO - created OSI model
EIA - electrical wiring, rack size
TIA - electrical wiring, cell tower, VOIP
ITU-T - video compression, IPTV, broad band communications, DSL
ICANN - coordinate IP Address allocation
-domain names used by DNS
-TCP/UDP protocol/port number
IANA - handles ICANNs job of
-IP address allocation
-domain name management
-protocol identifiers
TCP/IP and OSI model
-layered model used to help visualize interaction between layers
benefits of layered model
-assists in protocol design
-fosters competition
-prevents different layer changes from affecting other layers
-provides common language for network functions/capabilites
Two types of model
protocol model - closely matches structure of a particular protocol suite
-represents all functionality required to interface human network with data network
reference model - provides consistency within all types of networking protocols and services
-describes the what, not the how
OSI model TCP/IP Model
-----------------------------------------------------
Application
Presentation Application
Session
-----------------------------------------------------
Transport Transport
-----------------------------------------------------
Network Internet
-----------------------------------------------------
Data link
Physical Network access
OSI model designed by ISO
TCP/IP model deployed faster, so that it is what has been used
OSI model has specific functions at all layers
7. Application Layer - means for end to end connectivity between individuals in the human network using data networks
6. Presentation layer - provides a common representation of the data transferred between application layer services
5. Session Layer - Provides services to the presentation layer to organize its dialogs and to manage data exchange
4. Transport Layer - defines services to segment, transfer, and reassemble the data for individual communications between the end devices
3. Network Layer - provides services to exchange individual pieces of data over network between end devices
2. Data Link Layer - method for exchanging data frames between devices over common media
1. Physical Layer - Decribes mechanical, electrical, functional, and procedural means to activate, maintain, and deactivate physical connections for bit transmission to and from a network device
TCP/IP model (AKA Internet model)
defined by RFC
-contains technical and organizational documents
Application - represents data to the user, plus encoding and decoding control
Transport - supports communication between diverse devices across diverse networks
Internet - determines best path through the network
Network Access - controls hardware devices and media that make up the network
TCP/IP model is described in terms by the OSI model
-network access layer doesn't specify which protocols to use when transmitting
-only describes hand off
Data Encapsulation
segmentation - divide data into smaller, manageable, chunks
benefits - many conversations interleaved on the network
-increase reliability of the transmission
-more complex
multiplexing - interleaving the pieces as they traverse the media
data at any layer a PDU (protocol data unit)
data - application layer PDU
segment - transport layer PDU
packet - network layer PDU
frame - data link layer PDU
bits - physical layer PDU
data encapsulation - process of adding headers and trailers before transmission
deencapsulation - occurs at end devices
OSI model describes processes of encoding, formatting, segmenting, and encapsulating data for transmission over the network
network address -
-contains layer 3 information required to deliver IP packet from source to destination
L3 address has 2 parts
-network prefix
-host part
network prefix used by routers to forward packet to the proper network
host part used by routers to forward packets to the proper network
host part used by last router to deliver to final destination
a L3 IP packet contains 2 addresses: source, destination
Data link address
L2 physical address - used to deliver from one network interface to another network interface on the same network
on Ethernet, L2 physical address know as MAC or BIA (burned in address)
-48 bits
How does a host find MAC address?
uses ARP (address resolution protocol)
1) sending host send ARP request; broadcast to entire LAN
2) all devices examine the broadcast to see if it contains its own IP address
3) destination IP address device responds with ARP reply. ARP reply contains associated MAC address
Access remote network
1) sender determines destination is not in network
2) sends to default gateway
3) repeats 1 & 2 until reach destination
Monday, October 27, 2014
Information Density
I spent most of the last couple of days studying Cisco Introduction to Networks material. The chapter on IP addressing was incredibly dense. I ended up taking 25 pages of written notes during the entire thing.
I think what I learned from all of it is the future of the Internet is in the hands of two distinctly different people with distinctly different goals. One wants unlimited access to everything and no security. The other wants security.
There was a time when the Internet was time when the Internet was this wild, woolly place of hope and adventure. It was the great playground of intellectuals and only those in the know could manipulate the world. Which was great in theory, but not in practice. Eventually you ran into a human problem, not a technology problem.
I guess it narrows down to the simple fact that people want to get paid for their work. And the other group believes the Internet should be a free trading ground of ideas. I think both ideas are capable, but designing the Internet towards one or the other is short-sighted.
From a security standpoint, the argument is that with IPv6, you should use normal router and device hardening techniques and that should be fine. That idea was designed by someone who never had to protect a network, or anything for that matter. Security wise, you should always design for security in depth. There should be multiple, complimentary levels of security. Combining router hardening with NAT and PAT, VLANs, VPNs, network obfuscation and no DHCP pool and you've got the beginnings of security. I said beginnings, because each technology has its failings.
It's a big blue marble out there, and a lot of cooks with different plans make for an interesting mix.
I think what I learned from all of it is the future of the Internet is in the hands of two distinctly different people with distinctly different goals. One wants unlimited access to everything and no security. The other wants security.
There was a time when the Internet was time when the Internet was this wild, woolly place of hope and adventure. It was the great playground of intellectuals and only those in the know could manipulate the world. Which was great in theory, but not in practice. Eventually you ran into a human problem, not a technology problem.
I guess it narrows down to the simple fact that people want to get paid for their work. And the other group believes the Internet should be a free trading ground of ideas. I think both ideas are capable, but designing the Internet towards one or the other is short-sighted.
From a security standpoint, the argument is that with IPv6, you should use normal router and device hardening techniques and that should be fine. That idea was designed by someone who never had to protect a network, or anything for that matter. Security wise, you should always design for security in depth. There should be multiple, complimentary levels of security. Combining router hardening with NAT and PAT, VLANs, VPNs, network obfuscation and no DHCP pool and you've got the beginnings of security. I said beginnings, because each technology has its failings.
It's a big blue marble out there, and a lot of cooks with different plans make for an interesting mix.
Friday, October 24, 2014
No Blog is a Bad Blog
A Day late and a dollar short, here. I'm behind on pretty munch everything, which is why typing all this on a phone is kind of nicer. I can drag a blog out of myself where ever I happen to be.
I've taken a few pictures for something I'm thinking of about running cable. A Modest Mouse song about a long walk off a short pier keeps running through my head.
Then my wife was telling me something about a $100 bottle of wine, and I could think about was an Entreleadership podcast with Seth Godin. In that episode, he was discussing story telling and selling by pointing out that there isn't a wine out there where the cost of production alone justifies the high cost. If it only costs $5 to produce, then $100 wine doesn't make sense unless there is something else involved.
The other thing running through my head right now is one of Murphy's rules for combat. I found the document some time before the invasion in 2003, and it was pretty accurate. One of the statements was:
Yeah, seems pretty accurate.If you are low on eveyrthing except the enemy, you are in combat.
Wednesday, October 22, 2014
Cisco Introduction to Networks chapter 2 notes
Chapter 2
Configuring a network operating system
Router - forwards packets to and receives data packets from the Internet
switch - connects end devices using network cables
wireless access point -consists of a radio transmitter capable of connecting end devices wirelessly
firewall appliance - secures outgoing traffic and restricts incoming traffic
operating system enables the hardware to function
Cisco Internetwork Operating System (IOS)
IOS - generic term for the collection of network operating systems used on Cisco networking devices
kernel - portion of the OS code that interacts directly with hardware
shell - portion of the OS code that interacts with user and applications
user can interact with the shell through command line interface (CLI) or graphical user interface (GUI)
purpose of IOS
security
routing
QoS
Addressing
managing resources
interface
Accessing Cisco IOS
-console
-telnet/SSH
-Aux port
Console - outbound access - access via a dedicated channel for maintenance only
-available without configured networking services
telnet - remote access through a virtual interface over a network
-requires active networking on the device
-can also access any other devices via a built-in telnet client
SSH - secure shell - similar to telnet, but uses encryption
-stronger password authentication
-encrypts transmission
-requires active networking on the device
AUX - access via telephone dial-up
-requires no networking services to be set up
-can be used locally
Navigating IOS
user exec mode >
privileged exec mode #
global config (config)#
specific config modes (config-if)#
(config-line)#
user exec mode >
-view mode
-basic operations
privileged exec mode #
global configuration mode - change device as a whole
> enable/disable
#configure terminal
to leave modes -> exit or ctrl-Z
command structure
switch> ping 192.168.31.1
prompt command space keyword/argument
switch> show ip protocols
bold - type as shown
italics - supply value
Cisco IOS command reference
help forms
context-sensitive
command syntax
hotkeys and shortcuts
context-sensitive - provides a list of commands within the current context -> ?
command syntax check
-parse left to right
-generally only provides negative feedback
3 types of error
-ambiguous command
-incomplete command
-incorrect command
Hotkeys and shortcuts
ctrl+shift+6 ->break sequence
tab -> finish command
ctrl+C -> interrupts entry and exits config mode
commands
show - display various information
show version - display version info, system uptime, restart info
Getting Basic
Hostnames
switch requires no configuration to function
hostname - unique device name
-provide info about network setup
-remove ambiguouity
-should be used in network documentation
-create naming convention
-apply using CLI
Limiting access to a device
physical limitations - behind closed doors, in a rack
device passwords
enable password - limit access to priviledged exec mode
enable secret - same as enable password, but encrypts the password
console password - limit device access using password
VTY password - limit access via telnet
(config)# enable secret password
console security
#line console 0
#password ***
#login <- apply="" div="" login="" password="" the="" to="" used="">
VTY security
-most switches have 16 VTY lines number 0 through 15
#line vty 0 15
#password ***
#login <- div="" login="" on="" password="" require="">
->
#service password encryption
-applies weak encryption to all passwords when viewing configuration files
-removing command doesn't remove encryption
banner configuration
-should never show "welcome" type message, or encourage access
motd - message of the day
#banner motd # message goes in here #
-The # symbols are message start, end characters
-delimiting characters
-can be any character
-can't be in the message presented
-motd showed when anyone accesses the system
saving configurations
-running config reflects current operational configuration
-unsaved changes removed at reboot
#copy running-config start-config
#reload ->reboot system and restore to startup-config
eliminating startup-config
#erase startup-config
#erase NVRAM:startup-config
must also delete vlan file to return to factory out of box status
#delete vlan.dat
Backup configuration with text capture
#show running-config
copy/paste into a text file. Have to clean up file before importing back into a system
Address Schemes
Ports & Addresses
IPv4 (Internet Protocol, version 4) uses dotted decimal notation
-4 numbers between 0 and 255
-subnet mask also required
IP Addresses assigned to physical ports and virtual interfaces
-virtual interface - no physical hardware associated with the interface.
Addressing Devices
Remote access requires IP address and subnet mask
#interface vlan 1
#ip address XXX.XXX.XXX SubnetMask
ex... #ip address 10.75.20.254 255.255.255.0
#no shutdown <- and="" disable.="" div="" enabled="" ever="" port="" set="" t="" to="" won="">
->
Addressing End Devices
depends on device
-must have IP address,
subnet mask
default gateway
-default gateway is IP address of the way out of the network
-DNS server (domain name system)
translate IP addresses to web addresses
-IP addresses can either be configured manually or automatically using DHCP
Dynamic Host Configuration Protocol
Show IP info in windows using
ipconfig
ipconfig /all
testing the loopback
loopback adderss is 127.0.0.1 <-reserved address="" div="" ip="">
->
ping failure indicates problem with system
-drivers
-NIC
-TCP/IP implementation
Verifying connectivity
#show ip interface brief
use ping to verify end to end connectivity
-reserved>
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